Funding for this research was provided by:
General Research Fund of Shanghai Normal University (SK201720)
Funding Programs for Youth Teachers of Shanghai Colleges and Universities (A-9103-18-104001)
Ministry of Education, Humanities and Social Sciences Project (18YJCZH153)
National Statistical Science Research Project (2018LZ05)
Article History
Received: 8 June 2018
Revised: 18 November 2018
Accepted: 27 January 2019
First Online: 7 February 2019